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Last week I flew from New Jersey to Portland, Oregon, to get briefed by Intel PR reps and engineers about the company's next-generation CPUs and the new manufacturing process behind them. It was my first-ever visit to Intel's campus.

One of its campuses, anyway. I saw several peppered throughout suburban Portland, and that's not even counting the gargantuan Intel-branded factory construction site I jogged by the next morning, or Intel's other facilities worldwide. Usually our face-to-face interactions with tech company employees take place on neutral ground—an anonymous hotel room, convention hall, or Manhattan PR office—but two-and-change days on Intel's home turf really drove home the size of its operation. Its glory may be just a little faded these days, primarily because of a drooping PC market, tablet chips that are actually losing the company money, and a continuing smartphone boom that Intel's still scrambling to get a piece of, but something like 315 million PCs were sold worldwide in 2013, and the lion's share still has Intel inside.

That's what makes Intel's progress important, and that's why we’re champing at the bit to get the Broadwell architecture and see Intel’s new 14nm manufacturing process in action. The major industry players—everyone from Microsoft to Dell to Apple—depend on Intel’s progress to refine their own products. The jump between 2012’s Ivy Bridge architecture and 2013’s Haswell architecture wasn’t huge, but for many Ultrabooks it made the difference between a mediocre product and a good one.

Broadwell’s months-long delay has stalled this kind of progress (not that some haven’t tried to work around it anyway), but we’ll finally begin getting new chips later this year and into early 2015. Intel isn’t giving out specific performance or power consumption numbers for its new processors just yet (expect some of that at the Intel Developer Forum early next month), but the company has provided many more details on what we can expect.

The state of 14nm

Know your codenames

Codename and year

Process

Prominent consumer CPU branding

Tick/tock

Westmere (2010)

32nm

Core i3/i5/i7

Tick (new process)

Sandy Bridge (2011)

32nm

Second-generation Core i3/i5/i7

Tock (new architecture)

Ivy Bridge (2012)

22nm

Third-generation Core i3/i5/i7

Tick

Haswell (2013)

22nm

Fourth-generation Core i3/i5/i7

Tock

Broadwell (2014)

14nm

Fifth-generation Core i3/i5/i7, Core M

Tick

Skylake (2015)

14nm

TBA

Tock

Before we talk about the new stuff Intel is doing in its 14nm process, we should talk about the state of that process. Basically the only thing we've heard about it up until now is that it's the reason Broadwell is being held up. That delay, which was supposed to move the planned start of mass production from the fourth quarter of 2013 to the first quarter of 2014, was due to a "defect density issue" that was more difficult to fix than Intel anticipated.

There's good and bad news on this front. The good news is that Intel has 14nm production in what it deems a "healthy range," and the "lead product" for 14nm is in volume production and shipping to PC OEMs now—that would be the Core M, which we'll discuss in more detail later. "Further improvements" to the process are still being made, and, at some point in 2015, Intel thinks yields will improve to roughly the level that the 22nm process is at right now.

Enlarge/ Intel's chart here has no Y axis and isn't to scale, so it doesn't tell us a ton about where 14nm yield is relative to 22nm yield at the same point in its lifecycle—just that it's currently lower than 22nm was, but that it's expected to even out later on.

Intel

The bad news is that, whatever yields are actually at right now, they're not enough to support a launch lineup as large as the Haswell launch was last year. Intel announced 39 different Haswell chips across its quad-core and dual-core offerings at launch, ranging from low-voltage tablet and convertible parts all the way up to high-end desktop chips. Other chips waited until later (and some are still waiting), but they're the ones we've always had to wait for—budget Pentium and Celeron chips for desktops and laptops and Haswell-E/EP/EX Xeon chips for high-end workstations and servers.

Unsurprisingly, Intel is choosing to focus on the positive things here, and there's plenty about 14nm that looks pretty good for the company. Intel points out that its 22nm process had the lowest defect density of any process Intel ever used, despite some troubles early on. It's Intel's way of saying "hey, 14nm started a little rough, but we'll keep chipping away at the problems until we've cleared them up."

That said, yield is not expected to "meet the needs of multiple 14nm product ramps" until the first half of 2015. The Core M chips that are launching do a good job of showing what Broadwell can do that Haswell can't (and Intel tells us that PC OEMs are asking for them), but if Intel was in a position to replicate Haswell's relatively wide and smooth launch, it almost certainly would.

Transistors only do their job when there's current running through them. While early CPUs and GPUs simply ran the entire chip at its rated clock speed all the time, modern CPUs dynamically switch parts of the die on and off as needed, which is enabled by "gates." When the chip is idle, as much of it as possible should switch off in order to save power. When you need performance, everything should switch back on so you're not kept waiting. The gates also need to be able to switch between these states as quickly as possible.

Enlarge/ A standard "planar" transistor layout. Current travels through the inversion layer and is allowed through or blocked by the "gate," powering portions of the chip on and off.

The problem is, as you get to smaller manufacturing processors and attempt to fit more and more transistors into the same amount of space, the "inversion layer" that the power flows through (or doesn't flow through) gets much smaller. Less current can travel through the inversion layer when the gate is "open," and more current can leak through it to the other side of the gate when it's "closed."

Using 3D "fins" of silicon increases the surface area of the inversion layer, reducing current leakage when the gate is "closed" and facilitating power flow when it is "open."

One way to get around this problem—the way Intel is doing it now and the way other chip manufacturers are moving to in the next couple of years—is to use three-dimensional "fins" that protrude from the silicon substrate. This increases the amount of usable surface area for your inversion layer, so you can still power gate effectively while maintaining your transistor density. Intel is the only major semiconductor manufacturer who is rolling this kind of technology out in bulk at the moment, and, as the company is only too happy to point out, it is preparing to roll out its second-generation FinFET tech as competing fabs like TSMC and Samsung are still putting together their first.

In the 14nm process, the fins get taller and closer together. Fewer fins can accomplish the same work, increasing overall transistor density.

Intel

A close-up shot of the fins.

Intel

The 14nm process makes the silicon fins taller, giving them a little more surface area than before. This allows Intel to move the fins a bit closer together, reducing the total amount of space you need to use for fins. Intel says this allows for "improved density and lower capacitance."

Those altered fins and improved density are keeping Moore's Law (the number of transistors you can fit into a given amount of space will double every two years or so) alive for at least another generation. Intel claims it's keeping its costs down, too, something TSMC has reportedly had problems with. The cost-per-wafer of silicon is going up, but once the yield issues have been resolved, the increased number of processor dies Intel can harvest from a single wafer should keep prices steady.

Moore's Law continues apace.

Intel

Costs are staying relatively stable—the costs per wafer are going up at roughly the same rate that Intel can get more dies out of a single wafer.

Intel

More stats on Broadwell's shrinkage.

Intel

Intel

Intel

Whew. The takeaway is that Intel says it can deliver twice the performance-per-watt in 14nm Broadwell Core M chips as it could with 22nm Haswell Y-series chips. If you're a PC OEM, this should give you lots of flexibility: you could keep the performance and the size of your PC's chassis roughly the same and increase your battery life; keep the size of your PC and its battery life roughly the same and increase performance; shrink your PC while maintaining similar performance and battery life; or do some combination of all three.

Enlarge/ Like Haswell, Broadwell will eventually span across Intel's entire range of products, from slower but more battery-friendly chips like the Core M that can lower power usage to near-Atom levels, to higher-end chips like Core i7 and Xeon desktop and server parts.

Intel

Like the current 22nm process, Intel is planning to use 14nm to make chips going all the way up and down its product stack. It begins with Core M, but it will eventually extend to encompass Core i3/i5/i7 CPUs for laptops and desktops, Xeon chips for workstations and servers, and probably eventually some low-end Celeron and Pentium parts as well. The next Atom CPU architecture, a "tick"-style shrink of Silvermont named Airmont, will also use the 14nm manufacturing process.

We learned basically nothing about the 10nm manufacturing process that will succeed the 14nm process in two-or-so years—Intel would only talk about it to say that it wouldn't be talking about it. Any graphs where projections for it show up should be taken as shaky predictions at best. Intel has said that the 14nm delays shouldn't directly delay the rollout of 10nm, and that it will continue to refine the tri-gate transistor technology, but the company isn't talking specifics, and it's completely within the realm of possibility that 10nm runs into its own unique problems.

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Andrew Cunningham
Andrew wrote and edited tech news and reviews at Ars Technica from 2012 to 2017, where he still occasionally freelances; he is currently a lead editor at Wirecutter. He also records a weekly book podcast called Overdue. Twitter@AndrewWrites